Monday, June 10, 2013

Climate scientist Dr. Murry Salby explains why man-made CO2 does not drive climate change

Climate scientist Dr. Murry Salby, Professor and Climate Chair at Macquarie University, Australia explains in a recent, highly-recommended lecture presented at Helmut Schmidt University, Hamburg, Germany, why man-made CO2 is not the driver of atmospheric CO2 or climate change. Dr. Salby demonstrates:
  • CO2 lags temperature on both short [~1-2 year] and long [~1000 year] time scales
  • The IPCC claim that "All of the increases [in CO2 concentrations since pre-industrial times] are caused by human activity" is impossible
  • "Man-made emissions of CO2 are clearly not the source of atmospheric CO2 levels"
  • Satellite observations show the highest levels of CO2 are present over non-industrialized regions, e.g. the Amazon, not over industrialized regions
  • 96% of CO2 emissions are from natural sources, only 4% is man-made
  • Net global emissions from all sources correlate almost perfectly with short-term temperature changes [R2=.93] rather than man-made emissions
  • Methane levels are also controlled by temperature, not man-made emissions
  • Climate model predictions track only a single independent variable - CO2 - and disregard all the other, much more important independent variables including clouds and water vapor.
  • The 1% of the global energy budget controlled by CO2 cannot wag the other 99%
  • Climate models have been falsified by observations over the past 15+ years
  • Climate models have no predictive value
  • Feynman's quote "It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with the data, it’s wrong" applies to the theory of man-made global warming.

Professor Salby also explains in the 2012 edition of his textbook, Physics of the Atmosphere and Climate, why changes in global temperature control CO2 levels, not man-made CO2. Salby's findings corroborate the works of Humlum et alFr√∂licher et al, Cho et al, Calder et alFrancey et al, Ahlbeck, Petterssonand others demonstrating that man-made CO2 is not the driver of atmospheric CO2 or global temperatures.

As stated by Professor and Climate Chair Dr. Judith Curry,

"If Salby’s analysis holds up, this could revolutionize AGW science."
Selected slides from Dr. Salby's lecture: 
CO2 lags temperature
d13C levels have declined due to increased temperature, not due to man-made emissions
Satellite observations show the highest levels of CO2 are present in relatively uninhabited and non-industrialized regions, e.g. the Amazon, not over industrialized regions.
Net global emissions correlate almost perfectly with short-term temperature changes. d13C is inversely related to surface temperature. 
Methane is also controlled by temperature, not man-made emissions.
The IPCC claims that "All of the increases [in CO2 concentrations since pre-industrial times] are caused by human activity," but Salby demonstrates this is impossible.
You don't even need a climate model to show what climate models predict - projections are based upon a single  independent variable - CO2
Climate models have been falsified by observations over the past 2 decades.
H/T The Cold Sun [Google translation from German]:

Video recording of the lecture by Prof. Murray Salby in Hamburg on 18 April 2013

Professor Murry Salby, Chair of Climate Research at Macquarie University in Sydney, made ​​in a European lecture tour on 18 April 2013 held in Hamburg. Professor Salby is the author of the standard works "Physics of the Atmosphere and Climate" (Cambridge University Press) and "Fundamentals of Atmospheric Physics" (Academic Press) and is recognized worldwide as an atmospheric physicist. He has attracted attention recently with new findings on the relationship of the isotopes 12C and 13C, and the development of CO₂ concentrations. It is concluded that anthropogenic emissions have little effect on the global CO₂ concentration. They were mainly a result of temperature change. This relationship  was previously known only from the warming phase of the last ice age. Professor Salby extended this relationship to our current climate.
The video recording of the presentation is now available on YouTube. The opening words of the host Helmut Schmidt University are German, the lecture itself is in English.
See also our following blog posts with additional information on the topic:


  1. I don't see how some of this can hold up. For example, in the "CO2 lags temperature" graph above, for most of the peaks and troughs in the data it is the CO2 that obviously changes first, then the temperature. That anyone would claim otherwise is just unbelievable to me. And in the last sentence of this post, where it says CO2 change "lags the temperature curve", that cannot refer to the actual temperature record, because the temperature, globally, has no curve, no overall trend, for the last 15 years now (as yet another graph above clearly shows, and everyone in the debate knows as well as I). Such claims as these cannot "revolutionize climate science", and I suspect Judith Curry, like all the alarmists and "lukewarm" believers in the consensus greenhouse theory, is just clutching at straws in her statement above. The real revolution resides in the fact that there are no competent climate scientists, because they all cling to the failed, and incompetent, greenhouse theory (which my Venus/Earth temperatures comparison disproved with the definitive fact of two quite different planetary atmospheres, and provides a necessary fundamental correction to current false beliefs in climate science. I don't disagree with much of what Salby says in the above, but the results presented above are confused and therefore doubtful, and there is no appreciation for the Venus/Earth definitive evidence, which actually makes all the rest mere icing on an already accomplished revolutionary correction to the basic science (and Salby should know this, if he would write basic texts meant to educate the next generation of scientists).

    1. CO2 does lag temperature on short term timescales, as better illustrated by this graph with less smoothing:

      While Salby endorses the 'consensus' on CO2 greenhouse properties, he points out that 1% of the global energy budget allegedly from CO2 cannot control the other 99%, and that man is not the driver of atmospheric CO2 or the climate. This is an initial 'revolutionary' step for climate science, and hopefully more will follow.

    2. Salby also shows at 41:10 that human emissions are linear with a small increase over time, that the net emissions from all sources [shown above] does not look anything like the man-made emissions.

    3. Human emissions vary only 1-2% per year, while net global emissions from all sources vary "up to a couple hundred percent per year."

    4. Could you explain to me how he derived the graph with "net emissions"? Do we have such detailed data to make such a graph?

    5. As I have noted in a separate comment below, I believe Huffman is wrong in assuming that you have to compare the temperatures of Venus and earth at equal pressures, that is at 1 bar or lower. I sent him a comment about this on his blog but he did not post it and only referred to my reasoning as "incompetent theoretical arguments" without really discussing it. For others to read and judge my arguments I will give my explanation to why I think it is wrong here. It would have been better to do this on Huffman´s blog but since he refuses to keep an honest and open debate I turn to this forum since it seems to be open for comments by all perspectives.

      Please, if you do not agree with me let me know. I might learn something new if I am wrong.

      Huffman´s mistake is that he thinks pressure and temperature in the atmosphere is strictly dependent only on each other. The fundamental law, derived from both experiments and fundamental principles, which relates them in gases, is however p*V=n*R*T
      n=number of gas molecules
      R=gas constant

      So, pressure and temperature is also related by the number of gas molecules, which is directly related to density for a given volume. So you can change pressure without changing temperature if you change the density instead. This actually means that the temperature drop observed when going up in altitude, both on earth and venus, is not due to the drop in pressure. For instance we know that going up a mountain generally means it gets colder but even at high altitude and hence low pressure you can have temperatures higher than at lower altitudes and lower pressure.

      This independence of temperature and pressure is possible if dissipation of heat from a system can occur. Planets can do this to the surrounding space only by infrared radiation, not thermal conduction since this requires matter. Temperature will then be as low as the rate of heat addition to the system allows and this is mainly from absorption of visible radiation at the surface. For those who argue against the last point, see my further comment in my next reply to Huffman on this site.

      If these aspects are then true there is no reason to why the temperature of the planets should have anything to do with the pressure in the atmosphere so we dont have to do the comparison at 1 bar (maximum pressure observed on earth).

      To me it seems pretty clear that to compare the balance of energy input and output of the two planets you need to compare the highest average temperatures close to the surface regardless of pressure differences. Otherwise you are ignoring massive amounts of heat energy trapped by the surface and lower atmosphere of Venus. If you do this it is also clear that the temperature of Venus is much higher than earth and this can be explained by the green-house effect of CO2 but not solely by the difference in distances to the sun.

      It might seem like an amazing coincidence that Huffman´s analysis works but coincidences do happen even in physical sciences. The only way to tell a coincidence from a true physical phenomenon is if you can explain it and support the analysis by fundamental physical principles that have already been tested and verified by a scientific approach and/or to find enough experimental data that would out-weigh previous theories. Huffman has not tried to do this. Instead he suggests that we throw out all principles that do not agree with his conclusion. I am not prepared to do that. I can accept his observation that at 1 bar the temperature difference is not very big but to me this has no significance and is only a coincidence.

      Huffman has received some attention from people who, like him, doubt the green-house effect. That’s why I in a second reply to Huffman´s post here, if I am allowed, will give a qualitative but detailed molecular explanation to the green-house effect as I understand it. This has helped me to accept it as a true phenomenon.

      Let me know if I have been unclear about something or if you have better explanations.

      Best wishes

    6. Since it appears that some people still doubt the green-house effect I would briefly like to clarify the molecular mechanism of it as I understand it, since this has helped me to accept it as a true phenomenon. Huffman did not allow me to post on his blog unfortunately so I hope to do it here.

      The fact is that to convert electromagnetic radiation (i.e. light) into heat matter has to absorb it. Go to any basic textbook in physical chemistry or spectroscopy etc to read about this (I have used Atkins Physical Chemistry). Infrared radiation can be absorbed by gases such as CO2, H2O etc that exist in Venus and Earth atmosphere. When it is absorbed the molecules change their vibrational state, i.e. vibrate more intensely. This vibrational motion is kinetic energy of the molecule and this is what heat really is and this is measured by temperature. Note, the process is reversible so a molecule in a high vibrational state can emit a photon of infrared radiation and in the process decrease its kinetic vibrational energy. This is how earth and other planets eventually dissipate the heat provided by solar radiation to keep at thermal equilibrium. Heat conduction does not work in the vacuum outside the planets.

      Note, some of the emitted infrared light would be directed back to earth and could be absorbed by other molecules causing more intense vibration and hence higher temperature.

      Only so called infrared active molecules can absorb or emit infrared radiation, examples are H2O, CO2 etc but not N2 and O2 for instance. However the vibrational kinetic energy of infrared active molecules can be transferred to inactive molecules like N2 by collision making them either vibrate more intensely or receive a higher velocity i.e. translational kinetic energy, which is also heat. N2 would not be able to emit this energy as radiation but only be able to heat its surrounding.

      So if you introduce more infrared active gases (green-house gases, e.g. CO2) in an atmosphere more of the outgoing infrared radiation will be absorbed. Part of this energy will be emitted back towards earth to heat it and part of it to heat neighbouring molecules by collision. This would increase the temperature and hence the avereage vibrational state of all molecules. Then the rate of infrared radiation emittance will also increase until we reach a new thermal equilibrium where energy absorbed is the same as that emitted out to space, but now at a higher temperature. This is to my understanding how the green-house effect can cause global warming.

      Visible light, which is the main component of the electromagnetic radiation from the sun can also cause heating of matter but by a different mechanism involving electronic transitions. Importantly none of the gases in either earth´s or Venus atmospheres absorb visible light but the surfaces does.

      To be able to emit visible light a body would have to be at very high temperature. This follows the theory of black-body radiation and quantum physics of course. Earth is not hot enough to emit visible light but the sun is. The only way to dissipate heat from earth is by infrared radiation but if you keep more of this energy on earth of course the temperature will have to rise.

      Some would claim that due to reflection of the massive clouds on Venus little sunlight reaches the surface to heat it. Usually an albedo (how much light that is reflected away without being absorbed) of 60-70% is used so still 30-40% should reach Venus surface since no gases in the atmosphere absorb visible light.

      Even Salby agrees that the green-house effect is real but then the question is if mankind is able to influence it on earth or not, to cause global warming. I have made a comment below why I doubt his analysis, or at least parts of it.

      I hope the molecular mechanism of the green-house effect is clear and understandable from my description above. If not, let me know.

      Thanks for posting my comments! I am sorry for taking a lot of space but I hope to make it understandable to as many as possible.

      Best wishes

    7. Incorrect. Don't eyeball it, capture the graph and do first and second derivatives numerically

    8. Harry, just an observer. The graph is for C02 rate. The additional C02 is the integral of the rate and thus lags in the short term as the theory suggests. The rest of the comments re. long term C02 accumulation seem to be reasonable ie. The increased ppm is mostly from man made. The question for another discussion is whether there is significant increase in greenhouse to account for rising temperature. Measurements say no.

    9. Wrong, are you blind? CO2 lags behind temperature by 800 years.

      Buy some glasses.

  2. See ~44:00 for Salby's explanation why the satellite record demonstrates that d13C decreases due to natural sources such as vegetation [which are leaner in c13 vs. c12 just like fossil fuels], not due to man-made emissions of CO2.

  3. James Hansen on climate models: ‘It is a valid criticism-that there is a lot of physics that we may not even have in the models, and that which we do have in may be inaccurate’

  4. Hurry Dale Huffman's comment about the CO2 peaks leading temperatures makes sense on the face of it.
    However: the CO2 in the graph isn't really CO2 but its derivative vs time [d (co2)/dt] as is stated in the graph itself. it is the CHANGE in CO2 rather than its total quantity.
    since derivatives lag behind the function itself, it means the actual CO2 peaks lead the derivative curve such that the peaks occur where the graph (the derivative) cross the zero (more or less center between high and low peaks).
    if you now translate the derivative into CO2 quantities, the new graph peaks will LAG behind the temperatures.
    Dr. Salby is right after all.

  5. He removed CO2 but still grasps with tallon like hands the GHE theory. His model was the familiar K&T AR4 modified that is the flat earth with 24/7 sunlight from a cold sun. To claim, as he did, that TOA insolation is 340 odd W/m2 is stupid when the measured insolation is 1370W/m2 onto a rotating sphere. This relates to 500W/m2 at the surface when losses like albedo are taken out. To model reality you must use realistic inputs. the whole lecture was over an hour of my life wasted.

  6. The quote "It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with the data, it’s wrong" applies equally to Salby, and sadly the idea that the rise in CO2 is a natural phenomenon is directly refuted by reliable observations.

    For convenience, we can re-write Prof. Salby's mass balance equation in the form

    Let C' be the annual increase in atmospheric CO2, Ea represent annual emissions from anthropogenic sources, En annual emissions from all natural sources and Un uptake by all natural sinks (technically there is also Ua representing annual uptake by all anthropogenic sinks, but this is essentially negligible).

    Assuming conservation of mass (i.e. carbon doesn't spontaneously appear or disappear from the carbon cycle) then we can write

    C' = Ea + En - Un,

    Note that this is equivalent to an equation in Prof. Salby's Sydney Institute talk. We can rearrange this to give

    En - Un = C' - Ea

    So if the right hand side of this is equation is negative (i.e. anthropogenic emissions exceed the annual rise in atmospheric CO2) then the left hand side must also be negative (i.e. annual natural uptake must be greater than annual natural emissions). If we look at the observations from Mauna Loa and fossil fuel emissions estimates (both of which Prof. Salby says are reliable in his Sydney institute talk),

    we can see that the annual rise in atmospheric CO2 is always less than annual anthropogenic emissions (an observation well known as the "airborne fraction"), which means that for the last fifty years, natural emissions have been consistently less than natural uptake of CO2 from the atmosphere, i.e. the natural environment is a net carbon sink and has been OPPOSING the rise in atmospheric CO2, not causing it.

    The basic error Salby makes is looking for correllations between rates of increases. Correllations are not sensitive to the average value of a signal, but it is the average value that gives rise to the long term increase in atmospheric CO2, not the wiggles around the average value. The correllation that Salby has identified is well known and was first noted by Bacastow in 1976, and is described in the IPCC WG1 AR4 scientific basis report. A full explanation of this error can be found here.

    I emailed Prof. Salby a copy of the SkS article before it was published for his comment, but I recieved no reply. Following the mention of Prof. Salby's work on Judith Curry's blog, I emailed him a copy of my paper, which explains how we know the rise in atmospheric CO2 is anthropogenic, but I recieved no reply. For those who are interested, the paper is here:

    There are multiple lines of evidence that effectively rule out the possibility that the rise in atmospheric CO2 is a natural phenomenon, see

    As Fred Singer says, there are some skeptic arguments that have no scientific merit and are easily shown to be false, and that promulgating such arguments give skeptics a bad name. This is one of the arguments he lists.

    1. Sadly, your argument proves nothing, and you fail to understand all of the points made by Salby. No wonder he didn't bother to reply to your inquiry. Salby mentioned the mass balance argument and explains in detail why this is not evidence that anthropogenic emissions control atmospheric CO2 levels. For one, you fail to understand why decreased solubility of CO2 with increased temperature leads to net outgassing from the oceans. You fail to understand the obviously lagged relationship of CO2 to temperature, and that the cause does not follow the effect:

      Even hyper-alarmist James Hansen admits that the airborne fraction of CO2 has been on the decline for 50 years, despite an exponential increase in anthropogenic emissions, and he, like you, are scrambling to find an explanation that preserves AGW dogma:

      The airborne fraction of CO2 [the ratio of observed atmospheric CO2 increase to fossil fuel CO2 emissions] has decreased over the past 50 years [figure 3], especially after the year 2000. Hansen believes the explanation for this conundrum is CO2 fertilization of the biosphere from "the surge of fossil fuel use, mainly coal."

    2. This is such a stupid, static analysis error. Un is not wholly natural. The sinks are dynamic, and respond to both Ea and En. So, there is a portion of Un which is due to Ea, and a portion which is due to En. Call the former Una, and the latter Unn. Now, your equation is

      En - Unn = C - Ea + Una

      You have one equation, and two unknowns. That is not enough information to determine a unique solution.

      Why can I not get this through to you dolts? This is a feedback system. Un is dynamic. If Ea goes away, so does Una. It is wholly dependent on Ea. It is created and sustained by Ea. In every sense of the word, it is genuinely an artificial sink.

      I've led you and Ferdinand in detailed analogies looking at the rate of change, for example, of hot and cold water in a sink with a drain. I've demonstrated again, and again, and again, where your reasoning is flawed. And, still you serve up this bilge. Were you hit on the head as a child? What does it take to get through that thick skull? Is there anything inside?

    3. I gave an example here to show why this pseudo-mass balance argument is idiotic.

    4. Thanks Bart, appreciate your assistance & comments on many threads, from which I have learned much.

    5. If the oceans have been outgassing CO2 wouldn't you expect the oceans to become more alkaline?

    6. "the ocean is primarily a source of CO2 to the
      atmosphere, except during strong upwelling events."

      There is no reliable evidence that ocean pH has dropped:

    7. "If the oceans have been outgassing CO2 wouldn't you expect the oceans to become more alkaline?"

      No. The CO2 is not coming from outgassing of a static ocean, but from additional CO2 being trucked in my CO2 rich upwelling waters. There is more carbon being pumped into the system. Naturally, the oceans would become less alkaline.

  7. Post today by professor of applied mathematics Dr. Claes Johnson:

    The Dog and the Tail: Global Temperature vs CO2

    Prof. Murry Salby's presentation in Hamburg in April is a showcase of effective scientific communication based on mathematics. Salby gives strong evidence based on observation that the offset of concentration C(t) of atmospheric CO2 as a function of time t is determined by the offset of global temperature T(t) by an equation of the form
    dC/dt = T for all t > 0, C(0) = 0,
    after suitable scaling of C(t). In other words, C(t) is the integral of T(t), so that if T(t) = cos(t) then C(t) = sin(t) with a time lag of a quarter of a period.

    The fact that in the equation dC/dt = T the concentration C(t) is determined by T(t), comes out as an aspect of stability (or wellposedness): Integration is a stable or well posed mathematical operation in the sense that small variations in the integrand T(t) gives small variations in the integral C(t).

    On the other hand, differentiation is a an unstable or ill posed mathematical operation: small variations dC(t) in C(t) can give rise to large variations in dC(t)/dt as a result of division by a small dt. This means that viewing T(t) in the relation dC/dt = T to be determined by C(t) corresponds to an unstable mathematical operation.

    To make a connection from cause to effect in physics, requires stability and thus in the observed relation dC/dt = T, it is C(t) which is determined by T(t) as the cause and not the other way around. Another way of expressing this fact is to say that C(t) lags T(t) with a quarter of a period, so that variations in the cause T(t) precedes the effect as variations C(t).

    This is the observation from ice core proxies showing that temperature changes before CO2 and thus temperature is the dog and CO2 the tail with the dog wagging the tail, and not the other way around as the basic postulate of CO2 alarmism:


  9. The work presented by Murry Salby is a beautiful manifestation of inspired science without prejudice based on fundamental physical concepts and observation, established with solid mathematics and conveyed with striking simplicity and clarity. It is also open to constructive critique.

    This study follows previous ground-breaking work (tracked by long publication record on top peer-reviewed journals) on the relation between stratospheric ozone trends and atmospheric circulation as well as excellent education with his Atmospheric Physics textbooks.

    His current look on global warming and CO2 is frank, genuine and sensible, no surprise from the comments that is attacked by both extreme alarmists and skeptics, this actually proves that he is into something which might help reboot the AGW debate for the good of scientific truth and humanity.

  10. followup post by Dr. Claes Johnson today:

  11. As stated by Professor and Climate Chair Dr. Judith Curry,

    "If Salby’s analysis holds up, this could revolutionize AGW science."

    Uh, sorry, it will not.
    The AGW thesis is a political movement whose primary goal is to rein in big, bad, root-of-all-evil-in-the-world, CAPITALISM and in particular the USA.
    It is no coincidence that the AGW movement really took off when the USSR - after 70 years and their extermination of 20 million souls - went down into the toilet bowl, to the eternal mourning and crying of the Western world's eltist socialists and communists, almost all of whom never thought it worth their while to actually LIVE IN a communist nation despite having ample opportunity to do so.
    The AGW thesis, and it's most important concept - that CO2 is a pollutant, despite the fact that all plant life on the planet would perish as would all animal and human life - will NEVER die.
    Just as the religion of communism still has adherents, mostly among the "educated" and "elites" of the west, despite having caused the deaths of 100,000,000 million people in the 20th century, and is still worshiped by these Stalin/Hitler wannabes, so will AGW. It will never die, even if we all witness a one mile thick sheet of ice bearing down on the N.Hemisphere from the Arctic.

  12. I would say that Salby does not display some of his graphs properly. In the third image from the bottom he has put two graphs together in one with two different observables on two separate y-axes. The graph displays how temperature and CO2 levels has evolved over over the last 35 years. The problem is that he has adjusted the scales so that the CO2 level shoots through the roof while the temperature scale is set so that the small but clear overall temperature increase over the entire timescale appears negligible.

    If one would do as suggested the overall slope of the temperature curve, ignoring the large variations on short time-scales, will appear larger and the for the CO2 curve slightly lower. Then you would be able to properly judge for yourself if there is a correlation, as I would say there is even if it´s not very big. He claims there is no correlation at all.

    Salby manipulations of these graphs is, by my opinion, not fit for a scientist and cast doubt on his other points as well.

    Furthermore, the point that the increase and decrease of CO2 levels on short timescales (few years) lags the temperature is no surprise since, by the well established Henry´s law, solubility of gases in water decrease with temperature (leave a glass of cold water over night and observe the gas bubbles that form when the glass has warmed to room temperature). However, this does not disprove that there could be a substantial influence of CO2 on temperature on long timescales.

    When it comes to Huffman´s Venus/Earth comparison (see his comment above) I think he is wrong since he compares temperatures at different altitudes for the two planets. I have sent a comment to Huffman on his blog but have not received a reply yet nor has he published my comment.

    In fact, Huffman´s idea is based on absorption of incoming infrared radiation by the atmosphere and clouds on Venus and claims that this causes the heating of the planet. This absorption of infrared light by the matter in Venus atmosphere, which consist of 96% CO2, and conversion of its energy to heat is in fact the green-house effect that he denies exist.

    I am just starting to try to understand the details of this debate so will not comment further on other parts of Salby´s talk now.


    1. 1. Salby does not "manipulate" any graphs. You need to watch the entire lecture to understand the context. In brief, the climate models predict temperatures will increase 1:1 with CO2 levels, but this has not happened in the past [as shown by the 3rd graph from the bottom] nor during the 21st century

      2. Temperature leads CO2 on both short and long time scales [ice core data]. The cause does not follow the effect.

      3. The proper comparison is to compare temperatures at the same PRESSURE, not altitude, which is what Huffman does. He demonstrates pressure alone determines the temperature profile on both Venus and Earth. Almost no solar radiation reaches the surface of Venus due to opaque clouds.

    2. Thanks for posting my comment and replying to it!
      Please read my replies to your points below. My argumentations tends to be a bit long (sorry!) so I will divide it into three different replies.

      1. Unfortunately part of my text fell out in my previous comment so I fill it in here:

      My suggestion to make the graph more representable was to zoom in to the temp scale so that the temperature curve makes use of the whole vertical space available in the graph. Then it would be easier to see the overall temperature increase for the entire timescale. You need to average out the short time variations that appear to roughly oscillate around an average value over a few years. A crude way to do this is to draw a line in the centre of the short-time oscillations. I will still argue that the average temperature is 0.2-0.3deg higher 2012 compared to 1980. The value is small but non-negligible and would be easier to see and estimate if the graph was properly displayed.Furthermore, the CO2 axis should be adjusted so that the whole CO2-curve is visible within the graph.

      I can only speculate to why Salby did not do these adjustments but if he would have maybe people would have seen that there indeed is a small increase in temperature, which he tries to deny exists. At least to me his presentation of the graph is not honest so I distrust him as a scientist.

      Now to your comment: What do you mean by a 1:1 response?
      According to IPCC a doubling of the CO2 level would lead to about a 3deg (Celcius or Kelvin) temperature rise (the range they give is 1.5-4.5). In the graph mentioned a doubling of the starting CO2 level (340 ppm) would be 680ppm. The observed CO2 increase in the graph is about 60 ppm, that is one tenth of the doubling (8.8% to be exact). Again max CO2 value have to be roughly estimated since the CO2 curve is not properly displayed in the graph (see above).

      Note, one tenth of 3deg is as you realize 0.3deg, which is what I roughly estimated from the graph. So as I see it the graph shows what IPCC is arguing, even if my estimation is rough due to the oscillations. I am trying not to be biased in my estimation so please check yourselves and comment. I wish the scales and curves would have been better displayed so one could properly judge this.

      By the way, doesn't the melting of the ice-caps and permafrost slow down the heating? If so, the temperature increase might be considerably lower than expected at first but would increase more rapidly after the melting is complete. Does anyone know if IPCC or Salby takes this into account? It is maybe compensated for in the average temperature values?

      For my further comments see next reply.


    3. 2. I should rephrase myself: the lag in CO2 compared to temperature on both short and long time-scale is no surprise since it follows from the temperature dependence of solubility of gases. However, I don't think this necessarily have to mean that the CO2 can't influence temperature if we release enough of it by other means. The mechanism of release that we are causing is different from that of degassing of oceans.

      We might approach a state with unprecedented amounts of CO2 in the atmosphere, although Salby does not believe so if I understood him right. Here I think he might have a point but I did not follow the mathematical treatment completely so I will not argue about this view, only that the CO2-lag might not be relevant to disprove global warming by CO2 from other sources than degassing of the see etc. Indeed the oscillations should by my opinion be irrelevant, we should mainly worry about the absolute increase in CO2 and temperature over the entire timescale on which humans have emitted CO2 by combustion. The global average temperature 1850-2011 (figure nr 5 from bottom) also indicate an absolute total temperature increase. Of course this is not conclusive evidence that this is not a natural effect but should raise concern.

      Se also my last comment to your replies below.

    4. 3. I still think Huffman is wrong to compare temperatures at the same pressures for Venus and earth. Neither he nor you give convincing arguments for why this should be physically relevant. The only argument as I see it is that if you do it you get the result you want. Coincidences still happen even in physical sciences but the only way to tell a coincidence like this from a true phenomenon is by my opinion to be able to explain it by fundamental physical principles that have already been verified again and again by scientific approaches, or to find enough other similar cases that would out-weigh previous principles.

      Huffman still has not posted my comment I sent to him on his blog. He only replied that I used "incompetent theoretical arguments" but did not explain why he thinks so. I will submit my arguments as a reply to Huffman's comment above for other people to judge if my argumentation fails or not. I think this forum is more open to comments from all perspectives.

      To conclude my comments here I want to add that I am still trying to understand all the details of the IPCC conclusions. Maybe there is some truth to what Salby says. The potential implications of global warming is so huge however that you would have to make a much stronger case than he does not to act to prevent it. For me to trust his conclusions he should also present his arguments without introducing biased graphs like the one discussed above.

      Anyhow, oil will run out sooner or later. Then why not make the transition into a sustainable society now instead of taking a huge risk? If IPCC is correct we really have to act now since this transition will take a long time. The huge implications and short time-frame available for change is likely why consensus had to be a little bit forced. This is of course not desirable but might prove to have been necessary. The irony of it is that if we manage to change the situation we will never know if it would have been as huge a problem as proposed by some.

      Thanks for reading my comments and replying to them! Sorry for taking a lot of space!

      Best wishes

    5. In retrospect I must laugh at myself for writing these looong comments :):) I think no one will have the energy to read them, which is a shame because if I am wrong in something I will not know.

      Thanks for posting them anyway and for keeping this blog open to different views! I will try to keep this post short at least:)

      Best wishes!


  14. Martin said:

    "Let me know if I have been unclear about something or if you have better explanations."

    I think Martin has missed the point that as one goes up a change in density and pressure occurs within individual parcels of air but at the surface the density and pressure stays the same whatever the volume of the atmosphere.

    The reduction in pressure with height is therefore inevitably accompanied by a reduction of density with height which is itself dependent on the rate of pressure reduction.

    Martin should therefore not treat density as an independent variable.

    Consequently I think Harry's main point is correct.

    I am however puzzled by Harry's assertion that CO2 changes precede temperature changes.

    Stephen Wilde.

    1. Thanks for your comment Stephen! I like an open and honest discussion :)

      However, I don’t fully understand what you mean. I am not claiming that density is an independent variable. I am saying that temperature can be independent of the pressure if we can allow the density to change too. This can occur if the system under study can dissipate heat to the surrounding. So I do say that pressure and density is related here. This is what you are saying too with “The reduction in pressure with height is therefore inevitably accompanied by a reduction of density with height…”

      You can make an experiment to illustrate my point about the temperature. If you put a thermometer in a sealable plastic bottle (PET for instance) and allow it to thermally equilibrate with the surrounding the temperature inside the flask will be the same as the surrounding of course. Now, put a small piece of dry ice into the flask and seal it (use a very small piece if you do this for real since otherwise there is a risk of explosion). When the CO2 of the dry ice turns into gas the pressure and density will increase inside the flask. If you then, after all dry ice has sublimed, leave the flask to thermally equilibrate completely with the surrounding the temperature will still be the same inside the flask as in the surrounding but the pressure and density will now be larger inside the flask. So, the temperature does not depend on the pressure if the system can dissipate its energy to the surrounding. Planets can do this by emitting infrared radiation. If our planet would not be in thermal equilibrium by this kind of emission the temperature would increase until it reaches this equilibrium as I have explained in a previous comment on this site.

      My main point is that one should not compare the temperatures of venus and earth at equal pressures as Harry does. If you do, you are ignoring a lot of energy trapped as heat close to the surface of Venus. We know for a fact that the temperature at Venus surface is much higher than what can be explained by the distance to the sun when comparing to earth.

      As I see it, the only reason to do the comparison at equal pressures is that you then get a numerical correlation that seems too good to be a coincidence. However, coincidences do happen even in physical sciences and the correlation actually only exists for a limited set of data points. Furthermore, Harry has not been able to reproduce it for other planets or moons. So even if his observation is curious I would not make decisions influencing millions of people based on it.

      Best wishes

    2. The faulty statement that Venus is an example of the Greenhouse gas effect is shown by the fact that the planet has many active volcanoes, the surface temperature is above 500 degree C thus the IR radiated is at much shorter wavelengths than are absorbed by CO2. The radiated IR goes right through the 95% CO2 atmosphere and escapes into space or is absorbed by the sulfuric acid cloud surrounding the planet.
      This cloud of sulfuric acid filters out most of the EMR from the Sun such that the intensity of light reaching the surface is about 10% of the light intensity on Earth.

  15. Pertinent comment at WUWT:

    Magic Turtle says:
    July 9, 2013 at 3:13 pm

    When criticising Salby’s statements about CO2 Jan P Perlwitz (July 9, 2013 at 6:02 am) accuses Salby of ignoring the consequences of the mass-conservation law of basic physics. He writes:

    These “findings” could only be valid, if basic physical principles like mass conservation did not apply to carbon dioxide. Currently, about 32 Gt carbon dioxide are emitted by human activities every year. This would cause an increase in the atmospheric mixing ratio of carbon dioxide of about 4 ppm every year, if none of this carbon dioxide was removed from the atmosphere. However, the actual increase is about 2 ppm per year, currently. Since there are no substantial anthropogenic sinks of carbon dioxide, it follows from mass conservation and basic mathematical logic that Nature can’t be a net source in the carbon dioxide cycle of the planet under the present day conditions.

    and he concludes with the questions:

    Otherwise, if Nature was a net source for the carbon dioxide increase in the atmosphere, where did all the human carbon dioxide go then? Does carbon dioxide mass from human activities just mysteriously vanish?

    No, Mr Perlwitz, it is not Murry Salby who is ignoring the mass-conservation law; it is you (and the multitude of your fellow warmists) who are ignoring Henry’s law that governs the dissolution of gases in liquids. This well-established law of physical chemistry determines a fixed partitioning ratio between the amount of CO2 gas that the earth’s oceans will absorb and the amount that will remain behind in the atmosphere at equilibrium.

    The value of the partitioning ratio varies inversely with the water-temperature, ie. the warmer the water, the less it will absorb. At the current global mean ocean temperature of under 15°C the partitioning ratio is greater than 50:1. In other words, over 98% of all CO2 released into the atmosphere from whatever sources will ultimately be dissolved permanently in the oceans and less than 2% will be left behind in the atmosphere as a permanent addition to the resident CO2 greenhouse. Hence, Henry’s law deems that less than 2% of the approx. 4ppmv of CO2 that Perlwitz says is emitted annually by global industrial civilization will stay permanently in the atmosphere and the rest will go permanently into the oceans. Now 2% of 4ppmv is just 0.08ppmv. I do not see how any claim of a looming man-made global warming crisis can be justified rationally with that trivial annual greenhouse-increment of human-sourced CO2.

    So to Perlwitz’s simple question ‘…if Nature was a net source for the carbon dioxide increase in the atmosphere, where did all the human carbon dioxide go then?’, we can answer with a high degree of confidence that effectively at least 98% of it has gone into the oceans, leaving less than 2% behind in the atmosphere. It follows too that the remaining 1.92ppmv of atmospheric CO2 required to make up the total annual increase of 2ppmv (assuming that this estimate is correct) must have come from natural sources, Perlwitz’s views notwithstanding.

    The bottom line is that Henry’s law blows a massive hole in the alarmist AGW theory below the water-line. No wonder AGW-enthusiasts studiously avoid acknowledging it and are effectively in denial about it.

    1. As I read average ocean temperature increase from the publications from Argo buoys, the avg ocean temp has increased only 0.09 C. over 55 years. What does henry's law say about the quantity of C)2 this would outgas from the thermal layer of the ocean.?

  16. It's not up to those who don't believe that the "science is settled" to prove their argument; it is up to those who wish to impose an utterly unnecessary fee upon us all to explain exactly how AGW is a true threat to mankind as we know it.

    Is it even remotely possible that by 2100, there will be "no more humans" on the planet?

    The shenanigans of Mann, Jones,, along with the research of McIntyre, Watts, Costella and now Salby, are serving to stick a fork in the idea of AGW.

  17. John Costella, the author of the Climategate email analysis. Here is a link to the PDF:

    We still don't know the identity of the leaker, and that's probably best for that individual.

    I was remiss in not mentioning Ross McKitrick, Steve's co-author, and Christopher Monckton of Brenchley, among many others.

  18. satellite data agrees with Salby

    Net CO2 sources are from non-industrialized countries vs CO2 sinks in industrialized countries





    raw satellite data showing global land acts as net source of CO2


    and read further exchange that follows between Cogar & Courtney


    confirms Salby's graph above that the climate models are little more than linear assumptions of CO2 forcing


  26. Where is there a credible experiment that proves that the hypotheses of the greenhouse gas effect exists?
    Until someone comes up with such an experiment,everything else is either fantasy or circumstantial evidence.
    Albert Einstein once said, “No amount of experimentation can ever prove me right; a single experiment can prove me wrong.” Einstein’s words express a foundational principle of science intoned by the logician, Karl Popper: Falsifiability. In order to verify a hypothesis there must be a test by which it can be proved false. A thousand observations may appear to verify a hypothesis, but one critical failure could result in its demise. The history of science is littered with such examples.

    There is an experiment that proves that the Greenhouse gas effect does not exist. This experiment which has been technologically reviewed by Ph. D physicists . Ph. D. Chemical engineers and others Ph. D’s in other fields The experiment is found on the web-site http:// click on the blog tab then on page 3 of 12. . It is titled "The Experiment that failed which can save the world trillions-Proving the greenhouse gas effect does not exist” replaced by the following web-site: This web-site is being up-dated regularly with pertinent articles about the real science of the atmosphere.

    The Greenhouse Effect ExploredWritten by Carl Brehmer | 26 May 2012
    Is “Water Vapor Feedback” Positive or Negative?
    Exploiting the medium of Youtube Carl Brehmer is drawing wider attention to a fascinating experiment he performed to test the climatic impacts of water in our atmosphere.
    Carl explains, “An essential element of the “greenhouse effect” hypothesis is the positive “water vapor feedback” hypothesis. That is, if something causes an increase in the temperature this will cause an increase in the evaporation of water into water vapor.” The experiment shows that when there is more evaporation the atmosphere is colder.( This experiment proves that GHGE by the AGW is wrong)

  27. Man made global warming is demonstrably false:

    Key points:

    1. The Mediaeval Warm Period was hotter than today with much less CO2
    2. It hasn't warmed for 17 years.
    3. No mid tropospheric hotspot disproves the warmists' positive feedback hypothesis and proves the models wrong.
    4. No sea level rise increase.
    5. No sea temperature increase (ARGO buoy data).
    6. Outgoing Longwave radiation increases with surface warming cooling the planet (ERBE satellite)
    7. Low level cloud from water evaporation creates and albedo effect reflecting short wave radiation cooling the planet.
    8. Arctic ice was at a lesser extent thousands of years ago with far less CO2.
    9. Antarctic ice is at record levels.
    10. CO2 lags 800 years behind temperature rise in the climate record showing temperature drives CO2 not the other way round. (Vostok ice cores)
    11. GCMs (Global Circulation Models) are consistently producing results at least 3 times that of the observed temperatures, showing the models have their climate sensitivity parameter drastically wrong. In other words there are zero to negative feedbacks in the climate system, not positive as the models assume.

    BP and other fossil fuels do not fund skeptics. In fact they invest in renewables and emission schemes and merely pass the cost down to the taxpayer. They have a vested interest in the AGW scam, also they're largely owned by the bankers behind the scam.

  28. Some questions...

    1. If Salby is right and the ice core record vastly underestimates the CO2 ppm levels prior to the Mauna Loa era, can we find out what the *real* CO2 ppm numbers were, say, during the Holocene Thermal Maximum? One would think that if we can determine that the ppm levels were severely underestimated---especially the ones from thousands of years ago---then it would make sense that we could actually determine what these numbers should be relative to today.

    2. If CO2 tracks temperature as closely as Salby indicates, and if temperatures go down (as they are expected to in the coming decades), can we also expect CO2 levels to go down too? If/when that happens, wouldn't *that* be the paradigm-shifting moment?

    3. How does Salby's conclusions about the relative imminence of CO2 tracking to temperature fluctuations correspond with the ice core's well-established 800-year lag?

    1. 1. see stomata data & Beck's work:

      2. There are many things in the climate debate which should have been "paradigm-shifting", such as the "pause" in global temperatures, but haven't been due to the extremely well funded and entrenched climate aristocracy.

      3. CO2 is not the climate control knob and thus even if levels continue to increase it will have little effect on climate.

      4. CO2 follows temperature on short, intermediate, and long-term timescales. The cause does not follow the effect.

  29. New paper finding temperature, drought, and fires are the most important drivers of CO2 levels on inter-annual basis.

  30. U. Langer 14th October 2014 09:28
    Dear Mr. Kruger,

    So you want to prove that "the current CO2 increase is due to anthropogenic in our atmosphere."
    So just went through your points:
    . 1) The delta 13C value is not an argument for your thesis, as Mr Limburg has shown
    2) delta 14C value is also not an argument for your thesis, as Mr Wedekind has shown in # 6, what you have Mr. Kruger, in your answers but simply ignored. Here's a link for those who can not google: .
    (PS: I guess Mr. Kruger that your statement about the trustworthiness of Prof. E. Takle well (unfortunately) is meant sarcastically. But someone who holds such lectures: , I would not single files as reputable scientists So you should rather not believe everything unchecked, so what is this Lord himself - as image acquired by you. C-14 problem - classic cherry picking)!
    3) The O2 value drops parallel to rising CO2 levels. This is a correlation and not causality - so basically only suitable for the establishment, if any other cause can be ruled out for falling O2 values. But this is not the case. For natural CO2 emissions are bacteria (rotting organic material) an essential role. In this process, O2 is consumed at the same ratio as in the case of combustion. The annual variations of CO2 concentration show that this temperature-dependent natural process of determining process (and not the growing season, as you suppose). Thus, one can declining O2 content at least partially explained naturally.
    4) That lags behind the increase of CO2 concentration in the southern hemisphere the northern hemisphere, you can of course also explain, as the majority of the land is located on the northern hemisphere and local natural CO2 emissions (s. section 3)) cause such a delay.
    5) The allegedly remaining 55% of the anthropogenic CO2 amount is insufficient due cause your thesis. If you look closer namely, it is found that these 55% are only an average. The annual values ​​vary between zero and 100%.
    6) That is also expected to increase greenhouse gases other than analogy of course no real argument of their thesis.
    One can only conclude from your whole argument that human-induced CO2 emissions certainly contribute to but CO2 increase does not indicate that this post (almost) makes up 100% of the increase, but this is an existential acceptance of the AGW hypothesis.
    Their thesis is refuted.


    Google translation of

  31. Interesting battle going on... One question. How can CO2 molecule heat anything that is warmer than the CO2 molecule itself? If it can, greenhouse effect is true. If not, greenhouse effect is false.